Invasion and current distribution of the octocoral Carijoa riisei (Duchassaing & Michelotti, 1860) in the Ecuadorian coast (Eastern Tropical Pacific)

CÁRDENAS-CALLE, MARITZA; PÉREZ-CORREA, JULIÁN; UZCA-SORNOZA, CECILIA; BIGATTI, GREGORIO; LOZADA, MARIANA; KEITH, INTI

Aquatic Invasions

Regional Euro-Asian Biological Invasions Centre - REABIC

Lugar: Helsinski; Año: 2021 vol. 16 p. 62 - 76

Carijoa riisei is a snowflake coral that has aggressively spread across many coastalhabitats in the Atlantic and Pacific oceans, threatening a number of tropicalecosystems worldwide, including coral reefs. The aim of this work was to evaluatethe distribution and provide an estimation of abundance of the invasive octocoralC. riisei along the Ecuadorian coast, as well as the relationship between its abundanceand different environmental variables. In a field survey, high abundances of C. riiseicolonies were reported growing over corals and sessile communities at 5 of 43sampling sites. The areas with highest relative abundance were found in the Manabíprovince, at two sites in Jama: Bajo Londres (44.57% coverage) and Vaca Brava 1(20.25%). Results of ordination and grouping statistical analyses showed no significantdifferences between invaded and not invaded sites as regards community compositionor environmental characteristics, suggesting neither biotic nor abiotic factors couldbe limiting C. riisei dispersal along the Ecuadorian coast. Results from a bibliographicsurvey covering occurrence data up to 2020 were in accordance, showing that inthat period C. riisei became an established species to the Ecuadorian coast, beingpresent in at least 22 of the 43 sites, including various sites in Marine ProtectedAreas. Based on these findings, recommendations are made to promote urgentmonitoring programs to detect C. riisei in new areas along the coast of Ecuador andin the Galapagos Marine Reserve, in order to develop a mitigation program and totake actions to conserve the ecosystems affected by this invasion.